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The current study proposed a novel simple and environmentally friendly approach for producing silver nanoparticles (AgNPs) using an extract of Moringa oleifera leaves (MOL) and optimizing the different experimental factors required for the formation and stability of AgNPs. The formation of nanoparticles was confirmed by a color change from yellow to reddish-brown with a surface plasmon resonance band at 412 nm. The morphology, size, and elemental composition of AgNPs were investigated by zeta potential dynamic light scattering, field emission scanning electron microscopy, energy dispersive X-ray, X-ray diffraction, and transmission electron microscopy analysis, which showed crystalline and spherical AgNPs. The identification of functional groups was supported by Fourier-transform infrared spectroscopy. The photocatalytic activities of AgNPs were assessed in the degradation of organic Malachite green (MG) dye in the aqueous solution. Two kinetic adsorption models, the pseudo-first-order model and the pseudo-second-order model, and three isotherm models, the Langmuir, Freundlich, and Temkin, were used to mathematically characterize the MG degradation process. The pseudo-second-order kinetics and the Freundlich isotherm model were found to be in good agreement with the experimental data. As a result of their synergistic interaction with the MOL extract solution, the photocatalytic activity of AgNPs increases and they can successfully adapt to the photodegradation of organic dyes in industrial effluents.

Bacterial resistance to different antimicrobial agents is growing with alarming speed, especially when bacterial cells are living in biofilm. Hybrid nanoparticles, synthesized through the green method, hold promise as a potential solution to this challenge. In this study, 66 actinomycete strains were isolated from three distinct marine sources: marine sediment, the algae Codium bursa, and the marine sponge Chondrosia reniformis. From the entirety of the isolated strains, one strain, S26, identified as Saccharopolyspora erythrea, was selected based on its taxonomic position and significant antimicrobial activity. Using the biomass of the selected marine Actinobacteria, the green synthesis of eco-friendly silver carbonate nanoparticles (BioAg2CO3NPs) is reported for the first time in this pioneering study. The BioAg2CO3NPs were characterized using different spectroscopic and microscopic analyses; the synthesized BioAg2CO3NPs primarily exhibit a triangular shape, with an approximate size of 100 nm. Biological activity evaluation indicated that the BioAg2CO3NPs exhibited good antimicrobial activity against all tested microorganisms and were able to remove 58% of the biofilm formed by the Klebsiella pneumoniae kp6 strain.

This paper discusses the efficient implementation of a new hybrid approach to forecasting short-term PV power production for four different PV plants in Algeria. The developed model incorporates a time-varying filter-empirical mode decomposition (TVF-EMD) and an extreme learning machine (ELM) as an essence regression. The TVF-EMD technique is used to deal with the fluctuation of PV power data by splitting it into a series of more stable and constant subseries. The specified set of features (intrinsic mode functions (IMFs)) is utilized for training and improving our forecasting extreme learning machine model. The adjusted ELM model is used to evaluate prediction efficiency. The suggested TVF-EMD-ELM model is assessed and verified in various Algerian locations with varying climate conditions. In all examined regions, the TVF-EMD-ELM model generates less than 4% error in terms of normalized root mean square error (nRMSE).

The performance and response characteristics of simulated optical biosensor have been greatly enhanced in this work. The results were obtained by evaluating three different structures, each varying in the number of holes surrounding the cavity. The guidecavity coupling’s structural and dimensional characteristics were varied for an effective comparative study. The high sensitivity quality of this optical biosensor was achieved using large transmission rate. The results showed sensitivity around 800 nm/RIU in the first version, 800 nm/RIU in the second version, and 700 nm/RIU in the last version. Furthermore, the design parameters were optimized by finite difference time domain (FDTD) method. [ABSTRACT FROM AUTHOR]

This study introduces a cost-effective methodology to synthesize Ag@MCM-41 composites, utilizing petroleum sludge ash as a precursor. These nanomaterials exhibit well-structured arrangements and hold tremendous promise for applications in both photocatalysis and antimicrobial activities within the context of water treatment. The catalysts were subjected to thorough characterization using techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), and scanning electron microscopy (SEM) to assess their structural and optical properties. The XRD analysis corroborated the successful synthesis of orderly nanomaterials, while reflections corresponding to metallic silver planes convincingly demonstrated the effective integration of silver nanoparticles onto the MCM-41 surface, while simultaneously preserving its refined and ordered mesostructure. Subsequently, the photocatalytic performance of the composites was meticulously evaluated, and the results indicated exceptional degradation rates for MB, RhB, and MO dyes, by 15Ag@MCM-41. This degradation kinetic adhered to a pseudo-first-order model. Furthermore, the nanocomposite displayed remarkable photocatalytic stability across three reuse cycles, with a slight reduction in degradation efficiency observed during the third cycle. In addition to their notable photocatalytic attributes, all Ag@MCM-41 ratios demonstrated notable antibacterial activity against S. aureus and E. coli, as substantiated by the presence of an inhibition zone with a diameter of approximately 14 mm and 12 mm respectively. The nanocomposites we have developed in our current study hold significant promise within the realm of water treatment. They have the potential to serve as a low-cost tool for addressing two crucial aspects: the degradation of pollutants, such as dyes, from water effluents, and the inhibition of microorganisms in water systems. [ABSTRACT FROM AUTHOR]

Dyes are responsible for major environmental issues globally due to their toxicity, large-scale production, and extensive use in various industrial sectors. Pollution caused by hazardous dyes is mainly due to textile waste, which is constantly discharged into the aquatic system, often causing harm to humans and affecting water quality. In recent years, the removal of dyes from industrial textile wastewater has been a major challenge. Numerous technologies and methods have been developed to remove dyes from wastewater and meet clean water requirements. In this study, the effectiveness of activated carbon prepared by chemical activation of jujube stones for textile wastewater treatment was investigated. The effects of the concentration of H3PO4 and the carbonization temperature on the activated carbon's properties were studied. Several physicochemical methods, including Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction, methylene blue index, Boehm titration, iodine index and pH point of zero charge, were considered to characterize the produced adsorbents. To assess the quality of the two studied textile effluents (Mustard and Violet), the following parameters were used: biological oxygen demand (BOD), chemical oxygen demand (COD), turbidity, suspended particles and dissolved solids, before and after treatment with the produced activated carbon. Untreated wastewater analysis revealed high values for almost all parameters: pH > 9, COD of 302.72 mg/L and 230.68 mg/L for Mustard and Violet effluent, respectively. Both effluents from an industrial textile factory exhibited a COD/BOD ratio higher than three, which restricts their biodegradability. Examination of the effect of contact time and activated carbon dosage on the treatment of the two effluents showed that 4 g/L of activated carbon and 60 min of contact time were sufficient for optimal treatment, resulting in pollutant removal rates of 81.03 and 84.65% for the Violet and Mustard effluents, respectively. The results of this research highlight the efficiency of activated carbon derived from jujube stones as a cost-effective adsorbent for the treatment of real textile wastewater. [ABSTRACT FROM AUTHOR]

The present study focuses on investigating the adsorption characteristics of anionic Congo Red (CR) and Indigo Carmine (IC) dyes using hexadecyltrimethyl ammonium bromide‐modified Bentonite (HDTMA‐Bentonite) with varying loading amounts. The removal effectiveness of anionic dyes was examined as a function of the HDTMA+ loaded amount, contact time, initial concentration, and adsorbent dosage. The XRD data revealed that the interlayer spacing of Bentonite increased from 1.42 to 1.98 nm. The FTIR approach was used to analyze the surface modification of hybrid Bentonite; however, the hydrophobic nature of hybrid Bentonite was confirmed by ATG measurements. A kinetic investigation of sorption was done. The results demonstrated that the pseudo‐second‐order model fitted the adsorption kinetic data better than the pseudo‐first‐order rate equation, and that the amount of HDTMA+ loaded affects the adsorption capacity. According to the Weber‐Morris intra‐particle diffusion equation, the CR and IC dyes diffused faster as the amount of added cationic surfactant rose from 0 % to 100 % of the CEC value. Temkin and Langmuir equation is found to best represent the equilibrium data for two dye‐HDTMA‐B systems. Hybrid Bentonite was regenerated by NaOH, and reused without a significant decrease in its sorption efficiency, supporting the prosperity of its utilization as an effective adsorbent against toxic dyes from wastewater. [ABSTRACT FROM AUTHOR]